linux/arch/arm64/kernel
Dave Martin 159fd7b8d3 arm64/sve: Write ZCR_EL1 on context switch only if changed
Writes to ZCR_EL1 are self-synchronising, and so may be expensive
in typical implementations.

This patch adopts the approach used for costly system register
writes elsewhere in the kernel: the system register write is
suppressed if it would not change the stored value.

Since the common case will be that of switching between tasks that
use the same vector length as one another, prediction hit rates on
the conditional branch should be reasonably good, with lower
expected amortised cost than the unconditional execution of a
heavyweight self-synchronising instruction.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-17 18:19:53 +01:00
..
probes License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vdso arm64 updates for 4.15 2017-11-15 10:56:56 -08:00
.gitignore
acpi_numa.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
acpi_parking_protocol.c arm64: fix endianness annotation in acpi_parking_protocol.c 2017-06-29 11:33:15 +01:00
acpi.c More ACPI updates for v4.16-rc1 2018-02-09 09:44:25 -08:00
alternative.c arm64: alternatives: Add dynamic patching feature 2018-03-19 13:03:17 +00:00
arm64ksyms.c arm64: uaccess: Mask __user pointers for __arch_{clear, copy_*}_user 2018-02-06 22:53:40 +00:00
armv8_deprecated.c arm64: Remove duplicate include 2018-05-15 18:18:00 +01:00
asm-offsets.c arm64: assembler: add macros to conditionally yield the NEON under PREEMPT 2018-04-11 18:50:34 +01:00
cacheinfo.c arm64: Add support for ACPI based firmware tables 2018-05-17 17:28:09 +01:00
cpu_errata.c arm64: Move the content of bpi.S to hyp-entry.S 2018-04-11 18:49:30 +01:00
cpu_ops.c arm64: cpu_ops: Add missing 'const' qualifiers 2017-12-01 13:05:08 +00:00
cpu-reset.h
cpu-reset.S arm64: idmap: Use "awx" flags for .idmap.text .pushsection directives 2018-02-06 22:53:27 +00:00
cpufeature.c arm64: Increase ARCH_DMA_MINALIGN to 128 2018-05-15 13:29:55 +01:00
cpuidle.c ARM64 / cpuidle: Use new cpuidle macro for entering retention state 2018-01-02 13:50:34 +00:00
cpuinfo.c arm64: Expose Arm v8.4 features 2018-03-19 18:14:27 +00:00
crash_dump.c
debug-monitors.c arm64: Use arm64_force_sig_info instead of force_sig_info 2018-03-06 18:52:32 +00:00
efi-entry.S arm64: Add software workaround for Falkor erratum 1041 2018-02-06 22:53:13 +00:00
efi-header.S
efi-rt-wrapper.S efi/arm64: Check whether x18 is preserved by runtime services calls 2018-03-09 08:58:22 +01:00
efi.c efi/arm64: Check whether x18 is preserved by runtime services calls 2018-03-09 08:58:22 +01:00
entry32.S
entry-fpsimd.S arm64/sve: Write ZCR_EL1 on context switch only if changed 2018-05-17 18:19:53 +01:00
entry-ftrace.S arm64: Fix static use of function graph 2017-11-03 12:05:23 +00:00
entry.S 2nd set of arm64 updates for 4.16: 2018-02-08 10:44:25 -08:00
fpsimd.c arm64: Remove duplicate include 2018-05-15 18:18:00 +01:00
ftrace.c arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
head.S arm64/kvm: Prohibit guest LOR accesses 2018-02-26 10:48:01 +01:00
hibernate-asm.S arm64: assembler: Change order of macro arguments in phys_to_ttbr 2018-02-06 22:53:21 +00:00
hibernate.c arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables 2018-02-16 18:13:57 +00:00
hw_breakpoint.c arm64: hw_breakpoint: Use linux/uaccess.h instead of asm/uaccess.h 2017-12-12 11:53:26 +00:00
hyp-stub.S
image.h arm64/efi: Make strrchr() available to the EFI namespace 2018-03-05 13:45:38 -06:00
insn.c arm64: insn: Allow ADD/SUB (immediate) with LSL #12 2018-03-19 13:05:13 +00:00
io.c arm64: Avoid aligning normal memory pointers in __memcpy_{to,from}io 2017-10-24 16:23:07 +01:00
irq.c arm64: Add vmap_stack header file 2018-01-13 10:45:03 +00:00
jump_label.c
kaslr.c arm64/kernel: kaslr: reduce module randomization range to 4 GB 2018-03-08 13:49:26 +00:00
kgdb.c arm64/debug: Fix registers on sleeping tasks 2018-03-06 18:52:34 +00:00
kuser32.S
machine_kexec.c arm64: explicitly mask all exceptions 2017-11-02 15:55:40 +00:00
Makefile arm64: Move the content of bpi.S to hyp-entry.S 2018-04-11 18:49:30 +01:00
module-plts.c arm64/kernel: rename module_emit_adrp_veneer->module_emit_veneer_for_adrp 2018-04-24 19:07:35 +01:00
module.c arm64/kernel: rename module_emit_adrp_veneer->module_emit_veneer_for_adrp 2018-04-24 19:07:35 +01:00
module.lds arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
paravirt.c
pci.c PCI: Add a generic weak pcibios_align_resource() 2017-08-02 14:53:16 -05:00
perf_callchain.c arm64: unwind: remove sp from struct stackframe 2017-08-09 14:10:29 +01:00
perf_event.c arm64: perf: correct PMUVer probing 2018-02-20 11:34:54 +00:00
perf_regs.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
process.c arm64: uaccess: Fix omissions from usercopy whitelist 2018-03-28 15:25:44 +01:00
psci.c
ptrace.c arm64: Remove duplicate include 2018-05-15 18:18:00 +01:00
reloc_test_core.c arm64: fix undefined reference to 'printk' 2018-03-19 18:14:25 +00:00
reloc_test_syms.S arm64: fix undefined reference to 'printk' 2018-03-19 18:14:25 +00:00
relocate_kernel.S arm64: Add software workaround for Falkor erratum 1041 2018-02-06 22:53:13 +00:00
return_address.c arm64: unwind: remove sp from struct stackframe 2017-08-09 14:10:29 +01:00
sdei.c arm64: sdei: Add trampoline code for remapping the kernel 2018-01-14 18:49:50 +00:00
setup.c arm64: Move the async/fiq helpers to explicitly set process context flags 2017-11-02 15:55:41 +00:00
signal32.c arm64: uaccess: Fix omissions from usercopy whitelist 2018-03-28 15:25:44 +01:00
signal.c arm64: uaccess: Fix omissions from usercopy whitelist 2018-03-28 15:25:44 +01:00
sleep.S arm64: idmap: Use "awx" flags for .idmap.text .pushsection directives 2018-02-06 22:53:27 +00:00
smccc-call.S
smp_spin_table.c
smp.c arm64: capabilities: Change scope of VHE to Boot CPU feature 2018-03-26 18:01:41 +01:00
stacktrace.c arm64: fix unwind_frame() for filtered out fn for function graph tracing 2018-02-23 13:46:38 +00:00
suspend.c arm64: uaccess: Add PAN helper 2018-01-13 10:45:10 +00:00
sys32.c
sys_compat.c arm64: uaccess: Fix omissions from usercopy whitelist 2018-03-28 15:25:44 +01:00
sys.c mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff() 2018-04-02 20:16:11 +02:00
time.c arm64: fix unwind_frame() for filtered out fn for function graph tracing 2018-02-23 13:46:38 +00:00
topology.c arm64: topology: divorce MC scheduling domain from core_siblings 2018-05-17 17:28:09 +01:00
trace-events-emulation.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
traps.c arm64: only advance singlestep for user instruction traps 2018-04-24 19:07:36 +01:00
vdso.c arm64/vdso: Support mremap() for vDSO 2017-08-09 12:16:28 +01:00
vmlinux.lds.S arm64: remove no-op macro VMLINUX_SYMBOL() 2018-05-15 18:14:24 +01:00